A quantification method in quadrupole mass spectrometer measurement

Abstract

Quadrupole mass spectrometry (QMS) has been widely used in the semiconductor industry to monitor plasma radical or ion species, but the signal used in QMS is mostly not quantified. To quantify QMS signals to radical density measurements, the signals should be calibrated by a reference. During this calibrating process, it is important to apply a proper signal proportional coefficient between the signal of QMS and the particle density of the plasma, which is known to be strongly related to the mass of the particle, but is not precisely well known one until now. In this work, we propose a simple approach to obtain reliable signal proportional coefficients of different masses by using with standard gases, which are precisely specified components through gas manufacturing. This approach is expected to raise the reliability of quantifying QMS data, contributing to an advance in plasma database development.